Photocopy apparatus

ABSTRACT

A PHOTOCOPY APPARATUS HAVING A SHEET FEEDING MECHANISM, A LEADING EDGE DETECTOR, AND A PIVOTING COPY HOLDER. THE SHEET FEEDING MECHANISM CONSISTS OF A FLATTENED ROLLER USED TO DELIVER AN EXPOSED SHEET TO A DEVELOPER. THE FLATTENED PORTION OF THE ROLLER OBVIATES THE NECCESSITY OF MATCHING DRIVE SPEEDS BETWEEN ROLLERS IN THE DEVELOPER AND THE SHEET FEEDING ROLLER. THE EDGE DETECTOR CONSISTS OF A PAIR OF MOVABLE PHOTO CELLS. THE PHOTOCELLS ARE COUPLED TO A LOGIC BRIDGE CIRCUIT SO THAT, WHEN THE LEADING EDGE OF THE COPY PAPER COVERS THE FIRST PHOTOCELL, THE DELIVERY ROLLER IS STOPPED. THE DGE DETECTOR IS MOVABLE TO ALLOW ADJUSTMENT IN THE AMOUNT OF COPY PAPER TO BE FED TO THE EXPOSURE STATION.

0a. 26,1971 H, -,.-A B s ETAL 3,615,133

' fnowocom APPARATUS Original Filed Oct. 17, 1966 s Sheets-Sheet 1\MIRROR FIG.1

' Y INVENTORS.

HENRY N. FAIRBANKS DANIEL H. ROBBINS H. N. FAIRBANKS ETA!- PHOTOCOPYAPPARATUS Originzil Filed Oct. 17, 1966 5 Sheets-Sheet I5 FIG.5

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1N VENTORS HENRY N. FAIRBANKS DANIEL H. ROBBINS H. N. FAIRBANKSPHOTOCOPY APPARATUS 5 Sheets-Sheet 4.

Original Filed Oct. 17, 1966 INVENTORS. HENRY N. FAIRBANKS DANIEL HROBBINS ot.zs,1971 FMRBANKS my 3,615,133

PHOTOCOPY APPARATUS Original Fild Oct. 17, 1966 5-. Sheets-Sheet sINVENTORS. HENRY N. FAIRBANKS DANIEL vH. ROBBINS United States Patent3,615,133 PHOTOCOPY APPARATUS Henry N. Fairbanks and Daniel H. Robbins,Rochester, N.Y., assignors to Itek Corporation, Lexington, Mass.Original application Oct. 17, 1966, Ser. No. 587,248, now Patent No.3,472,590, dated Oct. 14, 1969. Divided and this application Apr. 24,1969, Ser. No. 828,063 Int. Cl. G03b 27/58 US. Cl. 35527 6 ClaimsABSTRACT OF THE DISCLOSURE A photocopy apparatus having a sheet feedingmechanism, a leading edge detector, and a pivoting copy holder. Thesheet feeding mechanism consists of a fiattened roller used to deliveran exposed sheet to a developer. The flattened portion of the rollerobviates the neccessity of matching drive speeds between rollers in thedeveloper and the sheet feeding roller. The edge detector consists of apair of movable photocells. The photocells are coupled to a logic bridgecircuit so that, when the leading edge of the copy paper covers thefirst photocell, the delivery roller is stopped. The edge detector ismovable to allow adjustment in the amount of copy paper to be fed to theexposure station.

This application is a divisional patent application of patentapplication No. 587,248, filed Oct. 17, 1966 for Photocopy Apparatus,now US. Pat. 3,472,590 issued Oct. 14, 1969.

The present invention relates to new and improved photocopy apparatus.

Photolithographic offset reproduction systems are known in the prior artwherein a photo-sensitive plate is positioned over an imaging platen.Graphic indicia to be copied is positioned upon an illuminated copyboard and the photo-sensitive plate is exposed by opening a shutter orturning on illumination devices for predetermined time periods. Theplate is thereafter developed and inked to form a master which in turnallows copies to be produced in an offset developing machine.

It is the principal object of the present invention to provide a new andimproved photocopying machine.

It is a further object of the present invention to provide a new andimproved photocopy machine that accurately feeds various predeterminedlengths of photosensitive media upon an imaging platen to accommodatevarying sizes of images to be reproduced without waste of thephoto-sensitive media.

It is a further object of the present invention to provide specialroller drive means for selectively feeding various lengths of exposedphoto-sensitive media into a developing processor, which special rollermeans operates on a fixed number of revolution basis, and need notoperate at the same drive speed relative to the drive speed of therollers associated with the developing processor and furthermore whichneed not be raised relative to the platen when the unexposed media isfirst fed to the imaging platen and lowered after the media has beenpositioned upon the platen.

It is a further object of the present invention to provide photocopyapparatus having cutting means which automatically cuts the exposedmedia just as it is being driven off of the platen onto the developingprocessor to obtain a clean cut and to prevent undesirable shifting ofkicking of the media owing to the cutting action.

It is a further object of the present invention to provide a photocopymachine having a pivotable copy board which protects the relativelyfragile illumination devices associated therewith when the copy board isexposed in its load position, requires little strength to manipulate anddoes not extend appreciably from the machine when in its open position.

It is yet a further object of the present invention to provide highlysensitive devices for detecting the presence of the leading edge of thephoto-sensitive media in order to halt the feeding of the media after apredetermined length has been fed to the imaging platen.

It is yet a further object of the present invention to pro vide a liquidprocessing bath for developing the exposed media where the quantity ofdeveloper liquid supplied to the processor is extremely low relative tothe surface area of the developed media thereby to preserve developerand reduce developer waste.

Other objects and advantages will become apparent as the followingdescription taken in conjunction with the drawings proceeds.

FIG. 1 discloses a side view of the photolithographic platemakingmachine.

FIG. 2 illustrates various features associated with the platemakingmachine.

FIG. 3 illustrates a second embodiment of the leading edge detectorillustrated in FIG. 2.

FIG. 4 illustrates a film processing both.

FIG. 5 illustrates a front view of the platemaking machine.

FIG. 6 illustrates a top view of the platemaking machine.

FIG. 7 illustrates various features of the pivotable copy board.

FIG. 8 illustrates a novel roller configuration.

Referring now to FIG. 1, cabinet 1 is disclosed having a glass imagingplaten 2, a mirror 3, lens system 4, and a pivotable door 6 having acopy board portion 7 thereon. Illumination means 8 are positioned belowcopy board 7 so \as to illuminate the indicia thereon. Lens system 4focuses images of the illuminated indicia on the imaging plane of glassimaging platen 2. A shutter device 8 is positioned along optical path 9for controlling the exposure of the photo-sensitive media 11 positionedupon the upper surface of glass platen 2. Door 6 is pivoted about pivotpoint 12 so that the indicia upon the copy board is changed or loadedtherein by pivoting door 6 until the door assumes the horizontallyoriented position illustrated at 13. Glass cover plate 14 is springbiased over foam rubber pad 16 to maintain the indicia accurately withinthe imaging plane. By squeezing latch members 17 and 18 toward oneanother, glass cover 14 is released and swung upwardly to facilitatemanipulation of. the indicia upon foam rubber plate 16'. Pivoted door 6is counterbalanced, since it is not pivoted at its bottom, to facilitatethe manipulation of the door. This arrangement is such that the lowerdoor portion 19 extends inwardly with respect to the machine so thatless of the door protrudes into the working area so as to conserve spaceand reduce the risk of bumping into the door. It is also to be notedthat the lower portion of door 19 in the open position covers thefragile illumination lights to eliminate the risk of breakage when thedoor is opened. After the copy board is loaded, latch members 17 and 18are squeezed together so as to again spring bias glass cover plate 14against the foam rubber pad 16. This may be accomplished in one motionwhile pivoting the door into its closed position. The particulararrangement of the copy board with respect to the aforementioned opticalelements result in a compact photocopy machine having a short opticalpath.

As shown in FIG. 2, a metallic plate 21 is positioned above imagingplaten 2 so as to roughly define the imaging plane. Cassette 22 having aroll of photo-sensitive media therein is positioned adjacent cuttingmeans 23 which is in turn positioned adjacent platen 2. Drive roller 24pulls the photosensitive media out of the cassette and into the imagingplaten upon being rotated by drive motor 26. A sequence timer 27 isschematically disclosed for controlling the timing of the variousoperational elements of the system. Timer 27 could consist of aplurality of commonly rotatable cams which coact with associatedswitches for sequentially marking various leads emerging from the timer.When timer 27 is in its home or reset state, conductor 28 is marked orenergized. The cycle is commenced by energizing conductor 29, byactuating pushbutton 31, which in turn causes drive motor 26 to drivethe media from cassette 22 into the imaging plane. The leading edge ofthe driven media passes under the flat portion of roller 32 and isthereafter detected by leading edge detector 33. As shown in FIG. 2,detector 33 is positioned adjacent slot 34 formed within platen 21 andincludes arm 36 pivoted about pivot point 37. The angular position ofarm 36 is adjusted by knob 38 depending upon the desired length of mediawhich is to be exposed. Photo-sensitive transducers B and A are mountedupon the pivotable arm and are connected to a comparator or logic bridge42 as shown. Illumination means 40, shown positioned below platen 2,illuminates the aforesaid transducer or photo cells. The leading edge ofthe photo-sensitive media as it arrives at detector 33 will sharplyattenuate the light detected by photocell A relative to the lightdetected by photocell B. The resulting unbalanced voltage applied tologic bridge 42 causes a stop signal to be forwarded to drive motor 26over conductor 44 so that feeding of film is halted upon the detectionof the leading edge by detector 33. An alternate detector which ishighly sensitive and yet rugged and reliable is illustrated in FIG. 3and comprises a cylinder 46 which is pivoted about pivot point 47 andwhich is mechanically coupled to microswitch 48. A feeler element 49which could take the form of a thin screw, rests upon the surface ofimaging platen 2 as shown. Since the mass of feeler 49 is small relativeto the mass of cylinder 46, it is apparent that the leading edge of themedia will readily cause cylinder 46 to be rotated to in turn causemicroswitch 48 to be closed thereby to stop drive motor 26. When theexposed media is thereafter driven off of imaging platen 2, gravity willcause member 46 to rotate back to its initial angular position. Withphoto-sensitive media which has considerable thickness such asphoto-lithographic plate material, the angular rotation will besuflicient to close microswitch 48'.

Timer 27 now actuates shutter relay 52 to expose the photo-sensitivemedia and thereafter cause conductor 53 to be marked to energize windoutmotor 54 and roller 32 coupled thereto. Knife motor 56 is also energizedat this time and the exposed media is cut by virtue of knife 23.Circular portion 57 of roller 32 contacts the media and commences topull it out of the imaging plane during cutting so as to preventundesirable shifting or kicking of the media which would otheriwse occurdue to the impact of knife 23 upon the media. Drive motor 58 whichdrives developer rollers 59 and 61 may be continuously rotating or maybe energized for an appropriate interval by lead 53 of timer 27. In anyevent, rollers 59 and 60 will be rotating when the leading edge of themedia arrives in developer processor 62. The control circuitry ofwindout motor 54- will cause this motor to make a fixed number ofrevolutions which will be sufficient to drive the shortest length of fedmedia into the bite of rollers 59. In the preferred embodiment,flattened roller 32 drives the media at 4 or inches a second whereas thedeveloper rollers drive the media at /2 inches a second. This disparitybetween driving speeds is made possible by the flattened portion ofroller 32. Since the drive speed of roller 32 may be greater than thedrive speed of roller 59, an increase in the loop length of the media atthe throat of processor 62 will result. However, near the end of eachwhole revolution of roller 32 its flattened portion will allow the mediato snap backward under the roller to thereby reduce the loop length andaccordingly no matching of the drive speeds of these rollers isrequired. Additionally, by virtue of this 4 snap-back action roller 32need only be rotated a fixed number of revolutions regardless of thelength of media fed out of the cassette so as to greatly simplify thedrive circuit controlling motor 54. For a one-inch diameter roller 32,the flattened portion is cut to shave A3 off of the diameter as shown.Lead 64 is thereafter energized to reset sequence timer 27 and therebyset the stage for the next cycle. It should be observed that sincecassette 22, knife 23, and platen 2 are positioned adjacent one another,there is little exposed media which is wasted should cassette 22 beremoved at the end of a particular cycle. In other words, in contrastwith prior art machines, fresh unexposed media is not delivered to theplaten as exposed media is removed therefrom and processed, but isremoved from the cassette only upon the initiation of a new cycle.

Processer 62 comprises a bulky bulbous guide member 63 which is bulkyenough so that its submerged volume is at least as great as the volumeof developer fluid contained within processor 62. The entire surface ofguide means 63 which is preferably smoothly continuous but may haveindentations therein, is impervious to processing fluid so that itdisplaces an amount of fluid equal to its submerged overall volume.Guide means 64 cause the media to closely follow the outline of guidemember 63 so that the volume of developer fluid present is extremelysmall relative to the surface area of the media processed in processor62. As a result, much smaller quantities of contaminated fluid aredrained from the processor than would otherwise be the case.

The above described embodiments being exemplary only, it will beunderstood that additions thereto, omissions therefrom and modificationsthereof can be made without departing from the spirit of the invention,and that the invention hereof comprehends embodiments differing in formand/ or detail from those which have been specifically disclosed.Accordingly, the invention is not to be considered as limited save as isconsonant with the recitals of the following claims.

What is claimed is:

1. Sheet handling apparatus comprising:

(a) a platen for receiving a sheet;

(b) sheet feed means including a roller having a fiattenedcircumferential portion and a curved circumferential portion, saidroller having physical dimensions such that the ratio of the length of aline extending from the roller circumference through the center of saidroller and perpendicular to the flattened circumferential portion ofsaid roller over the diameter of said roller is between .7 and .9,together with positioning means for maintaining the surface of theflattened portion of said roller separated from said platen with saidroller assuming at least one angular position and for maintainingportions of the curved portion of said roller in pressurized contactwith said platen upon rotation of said roller to other angularpositions.

2. The combination as set forth in claim 1 wherein said ratio is 3.Sheet handling apparatus comprising:

(a) a platen for receiving a sheet;

(b) first sheet feed means for advancing said sheet along said platen;

(0) second sheet feed means including a roller having a flattenedcircumferential portion and a curved circumferential portion togetherwith positioning means for maintaining the surface of the flattenedportion of said roller separated from said platen with said rollerassuming at least one angular position, and roller drive means forrotating said roller and for causing curved circumferential portions ofsaid roller to contact said sheet to drive it upon said platen with saidroller assuming other positions, and wherein said roller drive meansmaintains the flattened circumferential portion of said rollersubstantially parallel to the surface of said platen when said roller isroller is not being driven by said roller drive means.

4. The combination as set forth in claim 3 wherein said roller drivemeans maintains the flattened circumferential portion of said rollersubstantially parallel to the surface of said platen when said roller isnot being driven by said roller drive means.

5. The combination as set forth in claim 3 wherein the ratio of thelength of a line extending from the roller circumference through thecenter of said roller and perpendicular to the flattened portion of saidroller over the diameter of said roller is between .7 and .9.

6. The combination as set forth in claim 5 wherein said ratio is 6References Cited UNITED STATES PATENTS 2,764,069 9/1956 Bottoms 35564 X2,855,834 10/1958 Doster 355-64 X SAMUEL S. MATTHEWS, Primary ExaminerR. A. WINTERCORN, Assistant Examiner US. Cl. X.R.

